Vortex concentrator



Jan. 12, 1954 G, G, CHlsHOLM 2,665,809

VORTEX CONCENTRATOR Filed Feb, 9, 1950 2 Sheets-Sheetl l Jan. l2, 1954G. G. cHlsHoLM 2,665,809 VORTEX coNcENTRAToR Filed Feb. 9, 1950 2Sheets-Sheet 2 ffnenor Patented Jan. 12, 1954 VORTEX CONCENTRATORGilbert `Gr. Chisholm, Lucan, signor to Ferros Metals Ontario, Canada,as-

Research Company Limited, Toronto, Ontario, Canada Application February9, 1950, Serial No. 143,223

1 Claim.

' This invention relates to a vortex concentrator ofthe class which maybe employed for mineral separations. p

Previous cyclone devices have been employed for dust catching and in thecleaning of fine coal, particularly in a heavy medium. In previousconstructions the pulp is pumped into the cyclone structure which isusually in the form of a simple cone-shaped cavity having an outlet atthe bottom and an outlet at the top, the latter being in the region ofthe base of the cone. The pulp is introduced usually near the base ofthe cone and tangentially under pressure and the heavy or thickenedmineral sprays out the bottom end of the cyclone, the light overfiowforcing its way out of the opening in the upper regions of the base. y

A disadvantage in prior cyclone arrangements for these purposes is thatthe control in separation is not sufficiently definite by reason of theuncontrolled vortex action within the cyclone concentrator structure.

It is a principal object of the present invention to provide means forcontrolling the vortex action to more effectively control the separatingaction.

Another object of the invention is to provide a cyclone separator of avortex concentrator type embodying an inner cone that spreads the vortexof the pulp ow over a much greater surface than would be the case with anatural vortex thus giving a larger area of action and a more selectiveoperation against the pulp passing through the device.

A still further object of the invention is to provide an inner cone in acyclone concentrator wherein the sides of the cone are formed toconverge to a point substantially coincident with the theoreticalconvergent point of the inner surfaces of the cone of the cyclonedevice.

i A still further object of the invention is to provide means forfeeding a plurality of pulps into a concentrator or a plurality of mediaof different densities to more effectively control the separatingaction.

Other objects of the invention will be appreciated by a study of thefollowing specification taken in conjunction with the accompanyingdrawings.

In the drawings:

Figure l is a sectional view of an improved cyclone concentratoraccording to the invention.

Figure 2 is a sectional view of the concentrator of Figure l on the line2-2 thereof.

Figure 3 is a sectional View of a modified form of concentratoraccording to the invention includng a heavy media input.

Figure 4 is a sectional view of the device of Figure 3 on the line 4 4thereof.

Figure 5 is a diagram of a method of concentrating ore pulps employingcyclone concentrators according to the invention.

Referring to the drawings, and particularly to Figure l, the improvedconcentrator of :my invention comprises a relatively conventionalcyclone casing I0 having an input nozzle II arranged tangentially withrespect to the inner cavity I2 thereof, but having disposed therein theinner cone member I3 according to this invention, which serves to spreadthe vortex of the material moving within the casing over a much greatersurface to give a greater area of action and increase the selectivity ofthe device.

In detail, one practical form of structure may comprise an uppercylinder I4 having an outlet pipe I5 extending therefrom, The cylinderI4 has upper and lower flanges I6 and I 1. The upper fiange is fastenedto the closure plate I8 which forms part of the inner cone I3 and servesto locate the latter centrally within the casing I0. An intermediatecylinder I9 has mounted thereon the injector nozzle II which extendstherefrom tangentially as indicated in Figure 2. Suitable fianges 20 and2I are provided on the intermediate cylinder which match the flanges I1and 22 on the upper cylinder and truncated cone component 23respectively. The component 23 converges to terminate in a fitting 24carrying suitable threads 25 designed to mate with the threads 26 of thecontrol nozzle or concentrate regulator 21 having a port 28. I

It is particularly important to note that the inner surfaces 29 of thecone component 23 converge theoretically to the same point as the exterior surfaces 30 of the vortex regulating cone I 3.

In operation, the pulp is injected through the injector nozzle II underconsiderable pressure between the walls of the intermediate cylinder I9and the converging walls 3| of the pulp' divider 32 which is mounted bya flange 33 extending between the flanges I1 and 20 of the upper andintermediate cylinders. The tangential introduc- `j tion of the pulpunder pressure causes the pulpto circulate rapidly, thus setting upgreat cen-` As a result, the heavier frac-` trifugal forces. tions tendto move toward the walls of the intermediate cylinder I9 and at the sametime the; increased force of gravity caused by the cen-l trifugal forcedraws the pulp downwardly to" The', heavier fractions remain on theoutside whereas` wards the concentrate outlet port `28.

the lighter material remains about the vortex which is in the form of asmall air space extending about the converging surface 30 of the vortexregulating cone I3. The lighter fra-ctions tend to rise rapidly againstgravity through the annular space 34 between the pulp divider 32 and thesurfaces 30 of the vortex regulating cone I3, whereby the lighterfractions arise to` the annular chamber 35 in the upper cylinder andpass out of the device through the pipe I5' to tailings discharge.

The arrangement whereby the surfaces of the vortex regulating cone andthe lower cone component 23 converge to substantially a common point isimportant in that all forces are brought to a common point whereby theymay be easily regulated by the concentrate regulator 21. Asthe'regulator is screwed up the apex 36 or" the vortex regulating conepierces the outlet port 28 reducing the sectional area of the openingand thus causing the vortex created by the circulation of the pulpwithin the concentrator tovcarry a larger proportion of the pulp totailings discharge. The components just described, that is to say, theupper cylinder il), pulp divider 32, intermediate cylinder i9, and conecomponent 23 may be fastened together by passing bolts through the holesshown in the anges thereof and, further, the vortex Vcontrolling conemay be mounted in similar manner in conjunction with the upper flange I6of the upper cylinder i4.

A modification of the concentrator according to the invention isillustrated in Figure 3, the modification particularly embodying theprovision of a pulp divider skirt 3l of apparent greater depth than theskirt of the pulp divider 32 illus-y trated in Figure 1. The greaterdepth is necessary by reason of the inclusion of a heavy media ore pulpinjector 38 which is placed below the oreV pulp injector 39. In allother respects this structure is similar to that previously disclosed inFigure 1 but the modication embodying the heavy media ore pulp injectoris important in the control of separation.

The greater control will allow a cleaner conf centrate to be obtained inone operation. Thus, a heavy media pulp is injected at the same pressureas the pulp to be concentrated, the heavy media being injected throughthe injector nozzle 38 andthe pulp being injected through the nozzle 39.In using the device of Figure 3 in the separation of two minerals ofdiierent specific gravities, the latter as a pulp may be introduced intothe injector nozzle 39 and a separate medium of a specific gravityadjusted to a value between the speciiic gravity of the two minerals isintroduced by way of the heavy media nozzle 38. As a result, the lightermineral, in eiect, does not sink but is washed up and out of thecyclone. The heavier mineral is quickly drawn down by the amplifiedgravitational pull and passes out the Youtlet port 28 of the concentrateregulator The chief operating variables encountered involve the speciiicgravities of the pulp constit- Although the device oi Figures 3 and 4 ispresented as a modification which will allow a satisfactory concentrateto be obtained in one pass, it is preferred that devices of the typedisclosed in Figure 1 be employed in series. ''husy in Figure 5,`

a pump 40 draws pulp from a reservoir 4i Yand delivers it through theinjector nozzleinto a vortex concentrator 42 of the invention. Thelighter fractions pass out the pipe 43 to tailings discharge but theconcentrate is again pumped by a pump 44 and delivered under pressureinto a second' concentrator 45 similar in construction to theconcentrator 42. The lighter fractions discharged by this secondconcentrator are re-circulated by the line l5 to the ore pulp reservoir4|. The clean concentrate is delivered by the concentrator 45 asindicated.

A capacity of fifteen .tons per hour can be accomplished by constructinga device according to Figure 1 of a height of about 171/2 inches withquired for comparatively large capacities.

,g an overall diameter of about '7l/2 inches thus indicating therelatively small size of the unit re- The grading of the pulp may befrom minus 1/8 to less than 120 mesh and, in fact, the concentrator ofthis invention finds its greatest application in the separation of pulpsof a high degree of fineness greater than minus 120 mesh. It is Wellknown that gravity methods heretofore have not been particularlysuccessful in the separating of media of a iineness greater than minus120 mesh except by the use of cyclone concentrators, the latter being ona small scale. In mineral separation it is important that a maximumdegree of control be afforded in the separating action, this beingprovided in the construction of my invention by the inclusion of avortex control coneas disclosed herein, and further by incorporation ofa heavy media injector nozzle as disclosed herein.

There will be many modifications obvious to skilled persons in respectto specific details of: design of the concentrator unit disclosed'herein.

. It is thus intended that this invention should not be construed in anylimiting sense other than that indicated by the scope of the followingclaim.

What I claim as my invention is:

The combination in avconcentrator of the cyclone type having separatetailings and'concerb trate discharge openings, of: a vertically disposedvortex controlling cone converging downwardly to a point; a truncatedcone component, the side walls of which are disposed in spaced apart'rela tion to said vortex controlling cone, being cocone component havinga tailings discharge opening located at the upper end thereof; an inletto direct the pulp into said casing tangentially and disposed in saidcasing between theiconcentrate discharge opening and the truncated conecomponent; and a plup dividing skirt surrounding a portion of saidvortex controlling cone being in spaced relation thereto and including`Aa flange of annular form extending to the walls of said cylindric casingbetween the inlet port and the tailings discharge opening of the latterwhereby heavier fractions of pulp injected into said concentratorthrough theinlet port thereof rise through the space between said skirtari'd said vortex controlling cone in a manner controllable byadjustment of said nozzle of said tailings discharge opening withrespect to said vortexA controlling cone.

GILBERT G. CHISHOLM.

References Cited in the ille of this patent UNITED STATES PATENTS NumberName Date 2,504,944 Atkinson Apr. 18, 1950 FOREIGN PATENTS Number YCountry Date 809,570 France Mar. 6, 1937: M9985 Austria June 25, 1937886,187 France Oct. 7, 1943 608.026 Great Britain Sept. 8; 1948

